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Barbara Pease is the picture of femininity: slim, pretty, long blonde hair, an air hostess smile and a cute yet infuriating habit of scrunching up her face like an uncomprehending child at some of her husband's comments.
Infuriating, because as CEO of the couple's publishing firm Pease International, you imagine she's a reasonably smart, capable woman.
Yet the 44-year-old happily identifies with a stereotype that tightly - and fictitiously - circumscribes women's strengths and weaknesses.
"Barbara's a stereotypical female," confirms Allan. "She's low on spatials - knowing right from left, up from down... or which way is Starbucks."
The last is a dig at Barbara getting lost on a coffee mission from the couple's Auckland hotel room earlier that evening.
"No," Barbara demurs, "you gave me the wrong directions."
"You dilly," he laughs indulgently.
Meet the couple who between them have penned 10 pop psychology manuals and one joke book, four of which are dedicated to navigating the mysteries of the opposite sex. Why Men Don't Listen and Women Can't Read Maps sold more than 10 million copies. Why Men Don't Have a Clue and Women Always Need More Shoes was also a hit.
Their latest offering, Easy Peasey - People Skills for Life has chapters on "Manspeak" and "Womanspeak". In the pipeline is a book explaining why women want love and men want sex, and another on how to raise girls and boys differently.
"Men and women are dramatically different," explains Allan. Now 55, he blazed to fame at the age of 24 with his first book Body Language, which made him a darling of the chat-show and corporate training circuits. And contrary to findings cited in the Peases' books that women speak up to three times as much as men do, he does 95 per cent of the talking in this interview.
"Many women still believe that men somehow understand them... My 25-year-old daughter still believes boys understand her. There's this false belief that men and women are moving closer together."
The Peases' pitch is this: male and female brains have evolved to be profoundly different. Our mutual misunderstanding underlies most of our conflict. We can never truly "get" each other, but we can learn about our differences and strategies to manage them. The couple have combed through scientific research to distil those strategies for the masses.
It's worked for their own 18-year marriage, they tell me. Barbara: "We don't get angry and upset about the differences because that's the way they are, their brains are wired like that... You get the solutions to manage it. And that's what we do, we manage each other."
You have to give them credit. They've worked hard, beaten the odds. Both from poor state-home backgrounds, she ran a modelling agency and he was a record-breaking insurance salesman before they met. They have four adult children and a 2-year-old boy conceived using cutting-edge technology whereby eggs are fertilised with DNA material extracted directly from the father, rather than by his sperm - necessary after Allan had a vasectomy and prostrate cancer (he's survived two bouts of cancer).
Barbara is now carrying the 2-year-old's twin sister, whose embryo was frozen until earlier this year.
Their openness to such an unconventional technique is a little surprising, given their complete deference to "nature" when it comes to sex differences.
But for all their well-meaning advice and myriad fans, the Peases' teachings are part of an insidious slick of misinformation that's seeped into popular consciousness, a cult of sex difference blinding us to our true complexity and potential as individuals and the real similarities between men and women. To say nothing of the differences within the sexes.
Confession time: ever since John Gray's Men are From Mars and Women are From Venus, the myth of fundamental gender difference has done my head in. I've bored all my friends ranting about it - and probably offended a few. Look at people you know who contradict the stereotypes, I'd implore. The sensitive, diplomatic males; the decisive, ambitious females. Something in me - partly fear of never having a deep relationship with a male if he was really that alien, partly a horror of being strait-jacketed into a stereotype - rebelled. And the born-different thesis just seemed too tidy an explanation for gender prejudices and inequalities.
Though you don't often hear about it, there's strong evidence on my side.
In 2005, Wisconsin University psychologist Janet Shibley Hyde crunched results from hundreds of sex difference studies and found males and females, as groups, were overwhelmingly similar. Sex differences in stereotypical his/hers areas such as verbal and maths ability were small. Major differences only showed up in some motor measures, like throwing distance, and aspects of sexuality, such as masturbation frequency, while aggression showed a moderate gender difference. Also, the size of sex differences varied considerably across age and context. Another finding was that women were only 0.11 per cent more talkative then men, on average.
Pennsylvania University professor Mark Liberman and Oxford University professor Deborah Cameron have also debunked claims about women's yacking pre-eminence.
Cameron has pointed out that the garrulous female/conversationally challenged male stereotype was part of a trend in the 90s to define every problem - from marital breakdown to youth crime and domestic violence - as a communication problem. She's called it the "the triumph of therapy of politics, since it glosses over material questions of power and inequality. It suggests everyone means well and that we all have similar interests; there is no real conflict, only misunderstanding caused by verbal ineptitude."
And she laughs off the grunting-hunter/gabbing-gatherer theory evoked by the Peases. The little prehistoric evidence there is, she writes, suggests that hunting was rare, and gathering was done by both sexes.
Evolutionary psychology seeks to explain modern behaviour and experience in terms of general aptitudes and tendencies that might have paid off in the reproductive stakes 10,000 years ago, and so became programmed into our makeup.
But when you start mapping ancient, underlying impulses to behaviour as specific as remote-control hogging and the way you like your toilet paper to hang - as the Peases do - you're drawing an incredibly long bow.
"In many cases, the uses to which evolutionary theory is put are patently ridiculous," says Auckland University psychologist Virginia Braun. "But it's a very sexy theory right now."
And there are competing evolutionary stories. Socio-biologist Sarah Blaffer Hrdy compares women to their nearest living primate relatives, who are competitive, independent and sexually assertive when it's in their reproductive interests.
But the cult of difference does have its adherents within academia. The Peases draw on evolutionary psychologist David Buss, anthropologist Helen Fisher and geneticist Anne Moir. Former Harvard president Lawrence Summers kicked up a storm in 2005 when he suggested that "issues of intrinsic aptitude" could explain why there were so few women scientists and engineers.
This week, astronomer and BBC presenter Sir Patrick Moore harrumphed that British TV standards were deteriorating because the BBC was "run by women", and he called for separate channels for the sexes.
"I used to watch Doctor Who and Star Trek," the 84-year-old told the Radio Times, "but they went PC - making women commanders, that kind of thing. I stopped watching."
Why are we so obsessed with sex difference and so troubled by challenges to our pink and blue worldview?
Braun: "Why don't we focus on the overwhelming similarities [between men and women as groups] and the enormous differences between us, as people, rather than as representatives of our gender? What 'good' does this difference serve?"
For one thing, we're all prone to confirmation bias - focusing on evidence that agrees with our preconceptions and downplays contradictory evidence. For another, says Braun, academic journals are more likely to publish studies that produce a result - a difference between the compared groups - than those that don't.
Beyond that, there's a comfort in believing that boys will be boys and girls will be girls. But the cult of difference may be harming us.
In Same Difference: How Gender Myths Are Hurting Our Relationships, Our Children, and Our Job Rosalind Barnett and Caryl Rivers argue that sexual stereotyping stops us from reaching our potential and drives poor choices in our relationships, parenting and careers.
There's evidence that stereotypes can work as self-fulfilling prophesies: recent research showed that if women were told the sexes performed equally on a maths test, they did better than a comparison group who were told men outperformed women on the test.
Put these arguments to the Peases, and they wave them away.
Allen: "The first thing that's outstanding is most of that research... is presented by women."
He reels off a list of professions in which one sex predominates: air traffic controllers, relationship counsellors, pilots, accountants.
Barbara: "I don't think society tries to push people in those directions. They go there naturally."
They also have an explanation for why men outnumber women in the top jobs, even in female-dominated industries: women just aren't cut out to be CEOs, and men are.
Allen says Barbara's feminine prowess at "multi-tracking" (juggling numerous tasks) is invaluable for her CEO job.
"It's beyond me!" But, she seems to be an exception.
For while men are wired to be competitive leaders and derive self-worth from tangible results - money, status, promotion - women measure their success by the number and quality of their relationships.
Allan: "You've got to have a male-oriented brain to want to be a CEO in the first place...
"To be a CEO you have to give up things - relationships with your family, your kids, your partner.
"Most men are prepared to do that [because] men have always done that, they've always been the provider, out trying to beat other blokes. And women want men to be providers."
What about the glass ceiling?
"We reckon that's just a nice story created by feminists."
